Electric conductor.



N0- 805,249. PATENTED NOV 21, 1905.

L. E. UNDERWOOD.

ELECTRIC CONDUCTOR.

APPLICATION FILED APRJ, 1906.

WITNESSES! //-/a// /70/.

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UNITED STATES PATENT OFFICE.

LOUIS E. UNDERVVOOD, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC CONDUCTOR.

Specification of Letters Patent.

To all whom it may concern.-

Be it known that I, LoUIs E. UNDERWOOD, a citizen of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented certain new and useful Improvements in Electric Conductors, of which the following is a specification.

My present invention has for its object improvements in the means employed for connecting flexible conductors or pig-tails to conducting-bodies, such as the blocks of carbon employed as the brushes of dynamo-electric machines.

In carrying out my invention I form a recess in the conducting-body with a comparatively restricted passage or channel leading away from the recess and place a portion of the flexible conductor in the form of a bight or loop in the recess, with one or both ends of the loop or bight passing out of the recess through the restricted passage. The loop or bight may be secured in the recess by solder or in any other suitable manner. With this arrangement I obtain a large surface of contact between the flexible conductor and conducting-body. This insures a good electrical and mechanical connection between the flexible conductor and contacting body. Moreover, the arrangement of the bight or loop in the recess in the manner described tends of itself to prevent the separation of the flexible conductor from the conducting-body. A further advantage of this arrangement occurs from the fact that the flexible conductor is secured to the conducting-body at a distance from the place at which the flexible conductor extends away from the conducting-body. As

a result the flexibility of the flexible conductor at the point at which it leaves the contacting body is not impaired by the means employed for securing the two conductors together.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of my invention, however, reference may be had to the accompanying drawings and descriptive matter, in which I have'illustrated and described in detail forms in which my invention may be embodied.

Of the drawings, Figure l is a perspective elevation of a carbon brush with flexible conductor attached. Fig. 2 is a sectional elevation showing the brush and conductor of Fig. 1 before the solder is put in place. Fig. 3 is a section of the carbon block shown in Fig. 2, taken on the line 3 3 of Fig. 2; and Fig. 4 is a view similar to Fig. 3, showing a modified construction.

In the drawings, 1 represents a conductingbody in the form of a carbon block, such as a brush of a dynamo-electric machine. A recess 2 is formed in one side of the carbon block. The recess may be in the form of a hole drilled in the side of the carbon block. In the construction shown in the drawings the recess is arranged near one of the upper corners of the carbon block. A passage or channel leads from the recess 2 to the upper end or face of the carbon block. The passage or channel 3, which may be formed by a drill or in any other suitable manner, is considerably smaller in diameter than the recess. Preferably after the recess 2 and passage 3 are formed a coatingei, of copper or similar material, is electroplated on the upper end of the carbon block.

A portion of a flexible conductor or pig-tail 5, in the form of a bight or loop 6, is then placed in the recess 2, with the ends of the bight or loop passing out through the passage or channel 3. The bight or loop in the recess is preferably expanded, so that its outer surface engages the periphery of the recess, as shown in Fig. 2. The remainder of the recess is then filled with solder, which electrically and mechanically connects the flexible conductor to the carbon block. The film or coating A of copper on the carbon block facilitates the soldering together of the flexible conductor and the end of the block.

Instead of making the recess in the carbon block in which the loop or bightpf the flexible conductor is located in the form of a cylindrical opening, I may make it in the form of an annular groove 7, surrounding a central post 8, integral with the block, as shown in Fig. 4. In this construction the outer cylindrical surface of the groove 7 may be similar to the outer cylindrical surface of the recess 2 of the constructions shown in Figs. 1, 2, and 3. This arrangement increases the surface of contact between the flexible conductor and the carbon block over that of the constructions shown in Figs. 1, 2, and 3.

The outer ends of the flexible conductor may Patented Nov. 21, 1905.

be secured in a terminal clip 9 in the usual manner. As no effort is made to solder the portions of the flexible conductor 5 in the recess 3 to the carbon block, the flexibility of the pig-tail at the point at which it passes out of the outer end of the channel 3 is not impaired by the connecting means. This is an important advantage in many cases.

While I have hereinbefore shown and described the best form of my invention now known to me, it will be obvious to all those skilled in the art that changes may be made in the forms in which my invention are embodied without departing from the spirit of my invention, and I do not wish the claims hereinafter made limited to the exact construction shown and described more than is made necessary by the state of the art.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In combination, a carbon block havinga recess and a restricted passage leading away from the recess formed in it, and a flexible conductor having a portion in the form of a bight or loop located in said recess and an adjacent portion located in said restricted portion, said bight or loop being soldered to the carbon block.

2. In combination, a carbon block having formed in it a recess and a restricted passage leading away from the recess, and a flexible conductor having a portion in the form of a bight or loop located in said recess and an adjacent portion located in said restricted passage.

3. In combination, a carbon block having a hole or recess formed in one side and provided with a passage leading from said recess to another side of said carbon block, and a flexible conductor having a bight or loop in said recess and an adjacent portion passing through said passage.

4:. In combination, a carbon block having a hole or recess formed in one side and provided with a passage leading from said recess to another side of said carbon block, and a flexible conductor having a bight or loop in said recess and another portion passing through said passage, said bight orloop being soldered to the carbon block.

5. In combination, a carbon block having a hole or recess formed in one side and provided with a passage leading from said recess to another side of said carbon block, a flexible conductor having a portion in the form of a bight or loop arranged in said recess and portions passing through said passage, said bight or loop being secured to said carbon block, and a clip to which the ends of said conductor are secured.

6. In combination, a carbon block formed with a recess in it and with a restricted passage leading away from the recess, and a flexible conductor having a portion in the form of a bight or loop in said recess and another portion in said restricted passage, said bight or loop being secured to said carbon block.

In witness whereof I have hereunto set my hand this 30th day of March, 1905.

LOUIS E. UNDERIVOOD.

Witnesses:

JOHN A. MoMANUs, J12, HENRY O. VVESTENDARP. 

